可以反射用于实例化对象的基类的属性？ [英] Can reflection be used to instantiate an objects base class properties?

问题描述

这样的：

 公共类remoteStatusCounts：RemoteStatus 
 {
公众诠释statusCount; 
 
公共remoteStatusCounts（RemoteStatus R）
 {
型T = r.GetType（）; 
的foreach（的PropertyInfo中的p t.GetProperties（））
 {
 this.property（P）= p.GetValue（）; //例如伪
} 
} 
} 
  

的例子是有点简单（这是从吉拉API - RemoteStatus有4个属性），但想象中的基类有30个属性。我不想手动设置所有这些值，尤其是当我继承类只有一对夫妇的额外属性。

反射似乎在回答提示。

我看到在的http：// stackoverflow.com/questions/3072249/using-inheritance-in-constructor-publix-xy 我可以调用基类的构造函数（我想？纠正我，如果我错了），但我的基类没有按'吨有一个构造 - 它是从JIRA WSDL派生

 公共remoteStatusCounts（RemoteStatus R）：碱基（r）{//做东西} 
  

---

修改
我可以想象2有效的解决方案：上面概述，以及一些关键字像 this.baseClass 是类型（基类）和操纵正因为如此，作为一种指针，以这个。因此， this.baseClass.name =约翰尼将是完全一样的东西为 this.name =约翰尼

有关所有意图和目的，让我们假设基类有一个拷贝构造函数 - 那就是，这是有效的代码：

 公共remoteStatusCounts（RemoteStatus R）{
 RemoteStatus MBASE = R; 
 //做的工作
} 
  

---

EDIT2
这个问题不止一个思想的锻炼practial一员 - 我的目的，我可能已经很容易地做到了这一点：（假设我的基类可以使份）

 公共类remoteStatusCounts 
 {
公众诠释statusCount; 
公共RemoteStatus rStatus; 
公共remoteStatusCounts（RemoteStatus R）
 {
 rStatus = R; 
 statusCount = getStatusCount（）; 
} 
} 
  

解决方案

是的，你可以做到这一点 - 要知道虽然，你可能会遇到，你必须处理单独只吸气的属性。

您可以使用<$筛选它。C $ C> Type.GetProperties（BindingsFlags）超载

请注意：你或许应该看看代码生成（T4将是一个想法，因为它与VS 2008/2010交付），因为反射可以像执行速度运行时的影响。随着codegeneration，你可以轻松地处理这种单调乏味的工作，仍然具有相同的运行时间等喜欢手动键入下来

例如：

  //扩展方法某处
公共静态牛逼演员LT; T>（此对象o）
 {
回报率（T）O; 
} 
 
公共remoteStatusCounts（RemoteStatus R）
 {
型TYPER = r.GetType（）; 
型typeThis = this.GetType（）; 
 
的foreach（在typeR.GetProperties的PropertyInfo P（））
 {
的PropertyInfo thisProperty = typeThis.GetProperty（p.Name）; 
 
 MethodInfo的castMethod = typeof运算（ExMethods）.GetMethod（投）MakeGenericMethod（p.PropertyType）。 
 VAR castedObject = castMethod.Invoke（空，新的对象[] {p.GetValue（R，NULL）}）; 
 thisProperty.SetValue（这一点，castedObject，NULL）; 
} 
} 
  

Like this:

    public class remoteStatusCounts : RemoteStatus 
{
    public int statusCount;

    public remoteStatusCounts(RemoteStatus r)
    {
        Type t = r.GetType();
        foreach (PropertyInfo p in t.GetProperties())
        {
            this.property(p) = p.GetValue(); //example pseudocode
        }
    }
}

The example is a bit simple (it's from the Jira API - RemoteStatus has 4 properties), but imagine the base class had 30 properties. I don't want to manually set all those values, especially if my inherited class only has a couple of extra properties.

Reflection seems to hint at an answer.

I saw at http://stackoverflow.com/questions/3072249/using-inheritance-in-constructor-publix-x-y that I can call the base class constructor (I think? correct me if I'm wrong), but my base class doesn't have a constructor - it's derived from the jira wsdl

        public remoteStatusCounts(RemoteStatus r) : base(r) { //do stuff }

---

edit I can imagine 2 valid solutions: the one outlined above, and some sort of keyword like this.baseClass that is of type(baseclass) and manipulated as such, acting as a sort of pointer to this. So, this.baseClass.name = "Johnny" would be the exact same thing as this.name = "Johnny"

For all intents and purposes, let's assume the baseclass has a copy constructor - that is, this is valid code:

        public remoteStatusCounts(RemoteStatus r) {
            RemoteStatus mBase = r;
            //do work
        }

---

edit2 This question is more of a thought exercise than a practial one - for my purposes, I could've just as easily done this: (assuming my "baseclass" can make copies)

    public class remoteStatusCounts 
{
    public int statusCount;
    public RemoteStatus rStatus;
    public remoteStatusCounts(RemoteStatus r)
    {
        rStatus = r;
        statusCount = getStatusCount();
    }
}

解决方案

Yes, you can do this - be aware though, that you might run into getter-only properties which you have to deal with seperately.

You can filter it with the Type.GetProperties(BindingsFlags) overload.

Note: You probably should look into code generation (T4 would be an idea, as it is delivered with vs 2008/2010), because reflection could have runtime-implications like execution speed. With codegeneration, you can easily handle this tedious work and still have the same runtime etc like typing it down manually.

Example:

//extension method somewhere
public static T Cast<T>(this object o)
{
    return (T)o;
}

public remoteStatusCounts(RemoteStatus r)
{
    Type typeR = r.GetType();
    Type typeThis = this.GetType();

    foreach (PropertyInfo p in typeR.GetProperties())
    {
        PropertyInfo thisProperty = typeThis.GetProperty(p.Name);

        MethodInfo castMethod = typeof(ExMethods).GetMethod("Cast").MakeGenericMethod(p.PropertyType);
        var castedObject = castMethod.Invoke(null, new object[] { p.GetValue(r, null) });
        thisProperty.SetValue(this, castedObject, null);
    }
}

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